##DESCRIPTION
##   Algebra: Lines
##ENDDESCRIPTION

##KEYWORDS('Algebra', 'Lines')
##Tagged by up2p

##DBsubject('Algebra')
##DBchapter('Coordinates and Graphs')
##DBsection('Lines')
##Date('')
##Author('')
##Institution('Rochester')
##TitleText1('')
##EditionText1('')
##AuthorText1('')
##Section1('')
##Problem1('')

DOCUMENT();        # This should be the first executable line in the problem.

loadMacros(
"PG.pl",
"PGbasicmacros.pl",
"PGchoicemacros.pl",
"PGanswermacros.pl",
"PGauxiliaryFunctions.pl",
"PGgraphmacros.pl",
"extraAnswerEvaluators.pl",
"PGcourse.pl"

);

TEXT(beginproblem());
$showPartialCorrectAnswers = 1;

$x1 = non_zero_random(-6,6,1);
$y1 = non_zero_random(-6,6,1);

$graph = init_graph(-10,-10,10,10,'axes'=>[0,0],'grid'=>[20,20],'size'=>[200,200]);
$aline = FEQ("(-$y1/$x1)*x+$y1 for x in <-10,10> using color:green and weight:2");

plot_functions($graph,$aline);

BEGIN_TEXT

Find an equation \(y=mx+b\) for the line whose graph is sketched
$BR $BR
\{ image(insertGraph($graph), width=>200, height=>200) \} 
$BR$BR
The slope \(m\) equals  \{ans_rule(10)\}.
$BR
The \(y\)-intercept \(b\) equals  \{ans_rule(10)\}.
END_TEXT

$ans1 = -$y1/$x1;
$ans2 = $y1;

ANS(num_cmp($ans1));
ANS(num_cmp($ans2));

ENDDOCUMENT();        # This should be the last executable line in the problem.